DESCRIPTION: The applicant proposes to study the structure of a large number of human and animal viruses, virus interactions with receptors, antiviral compounds, and antibodies, as well as assembly intermediates by combination of X-ray crystallography and cryo-electron microscopy. Viruses to be studied include those from the picornavirus family, e.g., rhinovirus, coxsackievirus and poliovirus, and Mengo virus, and from the parvovirus family, e.g. human B19, MVM, porcine, canine and feline parvoviruses. The major focus is to study the interactions of the virus capsid with their receptors and antibodies, and structural changes involved in the process.